Fish Compatibility: Temperament, Size, and Water
Compatible fish share temperament, adult size, and water needs. A mismatch on any one of the three can turn a peaceful tank stressful.
What is the Fish Compatibility Checker?
Pick two fish from the built-in list and the tool reports whether they are generally compatible, cautious, or best avoided together. This is a general guide, not expert advice, since tank size, numbers, and individual temperament change real outcomes.
How to use it
- Pick the first fish.
- Pick the second fish.
- Click Check Compatibility.
Worked example
Guppies with neon tetras are generally compatible on this guide, given suitable tank size and water.
Why is a betta risky with guppies?
Bettas may mistake bright, flowing fins for rivals, which leads to chasing and fin damage even in a calm-looking tank.
Frequently asked questions
Is this expert advice?
No. It is a general guide from a small built-in list. Species research matters more.
Does tank size change compatibility?
Yes. A larger, well-planted tank with hiding places reduces conflict, while a small bare tank worsens it.